This invention is related to method and apparatus to controlling data between heterogeneous storage systems.
To achieve scalability for storage systems, “Scale-up” architecture and “Scale-out” architecture are generally used. Scale-up architecture can expand the system scale by installing storage components, for instance, controllers, cache memory, ports and disks. On the other hand, scale-out architecture can expand the system scale by connecting a plural of storage modules. Storage module includes controllers, cache memory, ports and disks. Such examples are disclosed in US2005/0144173A1, US2010/0070722A1. In scale-out architecture environment, the storage module may execute data migration function between two or more storage modules. This function is useful for storage replacing and load balancing, but is not applicable in cases where the storage system including the source volume has the data copy function, however where an other storage system including the target volume does not have the corresponding function. In addition, even where both storage systems have the data copy function, between heterogeneous storage systems data migration may not be performed because of the compatibility.
U.S. Pat. No. 7,386,598 discloses a method of creating a copy of a virtualized storage region. The server determines whether the storage unit system is capable of performing the copying operation, and if not the server would write the data onto the storage unit.
U.S. Pat. No. 7,228,380 discloses a method to connect a first storage system and second storage system, and provide the volumes in the second storage system to the host as external device of the first storage system. The storage connects external storages, mounts volumes of the external storage and provides a virtual volume by storing data to the external storage volume.
However, this method requires storage resources, such as ports, cache memory and processor time, of the first storage system to control the external volume compared to using the data migration function, which would not require storage resource of the first storage system after the data migration including the change of connection between the host and the storage system is completed.